Method of making socket wrenches



Feb. 1, 1944. w. w. HART-MAN 2,340,529

METHOD OF MAKING SOCKET WRENCHES Filed March 3, 1943' 3 Sheets-Sheet 1 vINVENTOR. VV/LLIAM VVALTEE HAETMA/Y m/VEV Feb. 1, 1944. w. w. HARTM ANMETHOD OF MAKING SOCKET WRENCHES Filed March 3, 1943 3 Sheets-Sheet 2 Ia. 7 W V; INVENTOR.

/L//4M AL A' 14197774 14 TOE/YE) Feb. 1, 1944. w. w. HARTMAN METHOD OFMAKING SOCKET WRENCHES Filed March 3, 1943 3 Sheets-Sheet 3 rmzz E6415ummmmn HM III a INVENTOR. VV/LL/AM M44472? fi/IETMA/V of this tube intothe desired blanks.

Patented Feb. 1,1944

METHOD or MAKING 'socxa'r wnENonEs William Walter Hartman, Los Angeles,Calif assignor of one-third to Evelyn Tylor Hartman and one-third toDavid Tylor Hartman Application March 3, 1943, Serial No. 477,788

(01. Hi-114i 14 Cl ims.

This invention relates to methods of makingsocket wrenches, and isconcerned particularly with simplification, speed-up, and savings instock in socket wrench manufacture.

The conventional method of manufacturing socket wrenches consists inboring a solid cylindrical bar of material to form a major diameteredopening extending inwardly from one end, and aminor diametered openingextending in from the other, and then breaching the walls of these twoopenings to shape them properly to fit respectiveiy a bolt head or nutand a square handle member. Such a method necessarily wastes a largepercentage of the stock, usually more than fifty per cent. Furthermore,these operations are both time-consuming and expensive.

The general object of the present invention is to provide a method ofmaking socket wrenches which eliminates the above-mentioneddisadvantages inherent in th conventional methods of manufacture.

A more particular object is to provide a method of making socketwrenches which virtually eliminates any wastage of stock whatsoever.

A further object is to provide a simplified, high speed method of makingsocket wrenches which eliminates machining, drilling, broaching or othersimilar expensive and time-consuming operations requiring skilledworkmen.

The method of the present invention, in a form adapted to themanufacture of one type of socket wrench, comprises first thepreparation of a tubular blank having interior bolt head or nut engaging faces and corners. While insofar as the broader aspects of theinvention are concerned, this blank may be produced by any desired typeof operation, it is a feature of the inven n, in

one of its more particular aspects, that these blanks be produced by anovel procedure comprising the drawing of a long cylindrical tube whoseinterior is shaped with longitudinal bolt head engaging faces andcorners of the conventional form, e. g., twenty four of such faces for atwelve point wrench, adapted to receive a polygonal bolt head or nut,and then the cutting These blanks, however produced, are mad ofpredetermined length, each being of a predetermined length greater thanthe length dimension of the final wrench to be formed. Finally, by anupsetting operation, the blank is shortened in length and one endportion thereof reduced about a square die member to form the squaresocketed handle-receiving portion of the wrench, the other end portionof the blank being meanwhile held taken through 4- 4 and 5-5,

to the initially prepared internal form. By this operation, the one endportion of the blank is converted from the initial interior conformationto a square socketed conformation, the shortening in length andreduction furnishing the stock required for this transformation, whilethe re-. mainder of the blank retains its initially prepared bolt heador nut engaging faces and corners. For the purpose of some wrenches inwhich it may not be desirable to reduce the outside diameter of thehandle receiving end, the stock required may all be obtained byshortening of the blank. The method may also be practiced in the moreinfrequent case in which it may be desired to have the handle receivingend of the wrench larger in diameter than the bolt head receiving end.In such case, the handle receiving end is both expanded and converted tosquare interior form, the blank being sufliciently shortened in theoperation to furnish the material required. Both of the indicated cases,however, involve the holding of the initially prepared interior bolthead engaging faces and corners in the bolt head receiving portion ofthe blank in substantially the initially prepared cross-sectionalconfiguration.

The invention will be better understood by now referring to thefollowing detailed description,

reference for the purpose being had to the accompanying drawings, inwhich:

Fig. 1 is a fragmentary levational view, and Fig. 2 is an endelevational view, of a drawn seamless tubing, the interior of which isshaped to accommodate a bolt head or nut of given size and illustratingthe result of the first or initial step in my method;

Fig. 3 is a fragmentary, partially elevational and partially sectionalview of a pressing or stamping die structure used to form the tubingblanks into socket wrenches, the die being shown in the beginning of itsoperation just before acting upon the tubing blank;

Figs. 4 and dare transverse sectional views respectively, of Fig. 3;

Fig. 6 is a fragmentary, partially elevationai and partially sectionalview of the die structure similar to Fig. 3, but showing the parts inthe positions assumed when the forming operation has just beencompleted;

Fig. 7 is a fragmentary partially elevational and partially sectionalview of the male die member after the forming operation, showing thecompleted socket wrench thereon and the action of the strippingmembers;-

Fig. 8 is a similar fragmentary partially elevational and partiallysectional view of the female die member when moved to its clear positionafter forming the socket wrench and indicating the ejector tube and itsaction should the socket wrench remain therein, the socket wrench beingindicated by dotted lines;

Fig. 9 is a fragmentary plan view of one of the stripping members thatcoacts with the male die member;

Figs. 10 and 11 are side and bottom views respectively of the finishedsocket wrench;

Fig. 12 is a view similar to a portion of Fig. 3, but showing amodification;

Fig. 13 is a section on line l3--i3 of Fig. 12;

Fig. 14 is a section on line "-44 of Fig. 13, the female die structurebeing omitted, and the view showing the finished wrench;

Fig. 15 is a view similar to a portion of Fig. 3, but showing anothermodification;

Fig. 16 is a section on line l6--|6 of Fig. 15;

and

Fig. 17 is a longitudinal sectional view of a socket wrench formed bythe die means illustrated in Figs. 15 and 16.

The initial step in one present illustrative form of my method of makingsocket wrenches con sists in forming, preferably by drawing, a seamlesstube of suitable steel, such as chrome molybdenum steel, to an outsidediameter equal to the desired outer diameter of the finished socketwrench, and with a bore or central opening 2 shaped to fit over apolygonal bolt head or nut. This tube is drawn hot by conventional meansand methods known to the art, and not necessary to set forth herein. Thetubing wall is preferably as thin as possible commensurate with thestrain to which the socket wrench will be subjected in service so thatit will fit into places having little clearance. If the socket wrench isintended to fit a hexagonal bolt head or nut, the bore 2 is preferablygiven what is known in art as a "twelve point form, that is, is formedwith twenty-four internal wrench engaging faces or facets f, arranged atangles to form twelve points" 3 and twelve corners or corner-receivingchannels 4 adapted to receive the corners of the bolt head or nut, sothat the bolt head or nut may fit in either of two positions. If thesocket wrench is then used to receive a square bolt head, the latter maybe received in any one of three positions.

The tubing I is next cut to predetermined lengths, preferably by use ofa cutting wheel, as indicated by the dotted lines in Fig. 1, formingblanks such as shown in section in Figs. 3 and 5.

The forming or upsetting die structure comprises a, male die member llset in a, base I! of a conventional press frame and a female dieassembly I3 carried by a press ram [4. The male die member H includes acylindrical lower portion 15 equal in diameter to the outside diameterof the blank 5. Above this is an intermediate portion I 6, which isexternally shaped in conformity with or complementary tothe interior ofthe blank 5, so that the blank will fit over it with a close slidingfit. At the juncture between the cylindrical portion 15 and the portionIS, the male die may be formed with a rudimentary beveled portion orfillet l1. Above the portion IS, the male die member is reduced indiameter, so as to form an upwardly facing shoulder lfia, above whichextends a stem H which is of the same cross-sectional shape as, andapproximatewhich is intended to be received within the wrench handlesocket. Thus, and as here shown. the reduced stem l8 may be square incross section.

The upper or female die structure l3 includes a female die block l9having a socket 20 in its lower end adapted to receive the blank 5 andthe cylindrical portion [5 of the male die member I I with a snugsliding fit, socket 20 being of a length equal to the finally desiredlength of the bolt head receiving portion of the finished socket wrench.Continuing from the inner end of the socket 20 is a bore 2| of reduceddiameter, being equal to the desired diameter of the finished handlereceiving portion of the socket wrench. The socket 20 and bore 2! areconnected by a fair-ed inclined shoulder 22, as illustrated.

Slidably fitted within the bore 2! is an ejector tube 23 having a squareopening 23a extending longitudinally therethrough and adapted to.accommodate the stem I 8 with sliding fit. The ejector tube is enlargedat its upper end forming a head 24, and between said head and the upperend of the die block is a spring 25 tending to hold the ejector tube inits uppermost position, as illustrated inFig 3.

The upper end of the die block I9 is reduced in diameter and externallythreaded to receive a cap block 26 having a bore 21 of sufficientdiameter to accommodate the head of the ejector tube. The cap block ispinned against rotation relative to the die block by a set screw 28 andthe side of the bore 21 is provided with a key 29 (see Fig. 3), coactingwith the head 24 of the ejector tube 23 to hold it in alignment withsquare stem l8.

The upper portion of the cap block 26 is reduced in diameter and fittedin the press ram I 4. An opening 30 is provided in the upper end of thecap block, this opening being of smaller diameter than head 24, so as toform an internal fiange limiting upward movement of the ejector tube. Aregistering opening 3| is provided in the ram l4, and the latter is alsoprovided with a transverse clearance slot 32. In the particular presshere shown for illustrative purposes, the press includes a fixedcrossbar 33 fitting within the slot 32 and carrying a stop pin 34, whichwill engage the upper end of the ejector tube when the press ram is inits upper position, as shown in Fig. 8, whereby the socket wrench,indicated by the dotted lines in said figure, will be ejected.

In the event that the finished socket wrench should remain fixed to themale die member instead of within the female die assembly, two or morestripper members 35 may be provided at the sides of the male die member.These may be moved into engagement with the lower edge of the socketwrench upon completion of the laterdescribed forming operation andsubsequent elevation of the female die assembly, by suitable means suchas a link and lever arrangement indicated generally at 36 in Fig. 3. Aswill be evident without the necessity of illustration, this arrangementmay be so inter-connected with the press, as for instance with the usualcrank, not

shown, that the stripper members will be auto-i matically advanced asthe press ram is elevated.

Operation of the forming die structure to form the blank 5 into thecompleted socket wrench is illustrated in Figs. 3, 6, 7 and 8. In Fig.3, the blank 5 is shown in position on the male die member and thefemale die block has descended to the point at which the blank is aboutto be engaged by the shoulder 22. Preferably, par- 7 ticularly if highalloy steels are used, the blank is heated to a suitable forgingtemperature before introduction into the die, and is thus in a conditionto be upset and formed as desired without undesirable weakening, as nowto be described.

Continued downward travel of the female die block below the position ofFig, 3 and to the position of Fig. 6 results in application of endpressure to the blank through engagement of the upper end of the blankby the shoulder 22 of the female die block, and consequent downward andinward deformation or upsetting of the upper portion of the blank untilit fully occupies the space between the square stem l8 and the bore 2|below the ejector tube 28. The volume of this space is calculated to bejust equal to the volume of metal of the blank projecting above theshoulder l6a, taking into the consideration the slight downward movementof the lower portion of blank 5 in order to conform to thebevel at H.The bevel I! may or may not be used, as desired, and it will of coursebe understood that if no such bevel is provided, there will be no suchslight downward movement of the lower end portion of the blank, asmentioned. Excepting for any such possible slight downward movementowing to the provision of such a bevel, the entire lower end portion ofthe blank is held precisely to its initial form and dimensions duringthe forming operation, the exterior diameter as well as the interiorwrench-engaging faces I preferably remaining unchanged throughout. Thelength of the blank as a whole, however, is substantially reduced, andthe upper end portion substantially reduced in diameter, while theportions of the nut or bolt head engaging faces 3 above the shoulder |6ahave been forced or displaced inwardly against the square stem l8, whichin effect defines the predetermined boundaries of the desired handlereceiving socket, so that now the interior opening of the upper portionof the formed socket wrench, designated by the numeral 5, has a squareopening or handle receiving socket conforming to the square stem I8. Atthe juncture between this square opening and the unchanged lower portionof the wrench is a downwardly facing shoulder, as clearly appears inFig. 6, while the outside of the wrench has a tapering shoulderconforming to the die shoulder 22 connecting the unchanged lower portionof the wrench with the reduced portion 1, all as clearly shown in thedrawings.

The single described movement of the die structure thus completes theforming operation. When the male and female die members separate, thefinished socket wrench 6 may remain on the male die as indicated by thesolid lines in Fig. 'l, or within the female die block as indicated bythe dotted lines in Fig. 8. In the one case, it will be loosened by thestripper members 35, and in the other, by ejector tube 23.

The finished socket wrench 6 is illustrated in Figs. 10 and 11, and asfinished, has a reduced portion I formed with a square handle-receivingopening 8 therein, the portion 1 being connected by the describedtapering shoulder portion with the nut or bolt head receiving portion ofthe wrench, which both internally and externally remains in the form ofthe initially drawn tube I.

Attentionis particularly called to the fact that there is no wastage ofmaterial whatsoever beyond the negligible amount involved in severingthe tube I into the blanks 5. Moreover, the

manufacturing operations are reduced toa minimum, and completed socketwrenches may be manufactured at a substantially increased rate ofproduction as compared with heretofore known methods of manufacture. Thecompleted wrench, while utilizing a minimum of material, is inherentlystrong in its completed form, and compares favorably in appearance andstrength with wrenches manufactured by slower and more costly priormethods.

Figs. 12, 13 and 14 show a modification of the die structure by whichsocket wrenches may be manufactured in accordance with the inventionwithout reduction in the diameter of the handle receiving portionthereof. Numeral 5 again designates the blank, and it is to beunderstood that this blank may be the same as the blank j formed andutilized in the previously described form of the invention. Numeral l l'designates the male die member, including cylindrical lower portion l5,equal in diameter to the outside diameter of the blank, intermediateportion l6, externally shaped in conformity with the interior of theblank 5, and stem l8 of square cross-section extending upwardly aboveportion I6. This entire male die assembly, and the base therefor, may beexactly similar to that shown in Fig. 3, with the exception that thestem 18' is enlarged so that its diagonal dimension is just equal to theinternal diameter of the blank measured between corners I. The blank 5will then just receive the stem II with a sliding fit, as will bereadily understood by an inspection of Fig. 13.

The upper or female die sector includes female die block l9, onlyfragmentarily appearing in Figs. 12 and 13, having socket or bore 20adapted to receive the, blank 5 and the cylindrical portion iii of dieII with a snug-sliding fit. This bore 20' is not reduced, as in the caseof Fig. 3, but is to be understood as extending upwardly throughoutblock [9' at uniform diameter. In other words, the socket 20 and reducedbore 2| of Fig. 3 are substituted for by a continuous bore 20 of uniformdiameter extending from bottom to top of the die block l9.

Slidably fitted within bore 20 is tube 23' having square opening 23aadapted to accommodate stem l8 with sliding fit. This tube 23' will beunderstood as corresponding entirely to tube 23 of the form of Fig. 3,excepting for the enlargement in diameter necessary to afford thesliding fit within bore 20', and excepting for the further fact that itslower end has not only an ejecting function, but also the function ofupsetting the blank to conform it to the stem I8. Excepting for themodifications appearing in Figs. 12 and 13, the die structure may beentirely similar to that illustrated in Fig. 3. The modifled operationof the form of Figs. 12-14 is as follows: In the downward travel of thedie block i9 and tube 23', the lower end of the latter engages the upperend of the blank, resulting in downward and inward deformation of theupper portion of the blank until it fully occupies the space between thesquare stem l8 and the bore 20 below the lower end of tube 23'. Theresult of the operation is illustrated in Fig. 14, the blank having beenshortened and the metal thereof moved inwardly above male die portion I6' to conform to the square stem H3. The finished socket 6', not yetremoved from the male die member in Fig. 14, is entirely similar to thesocket, wrench 6 of Figs. 10 and 11, with the sole exception that theoutside diameter of its upper handle-socketed portion has beenmaintained at the initial outside diameter of the original blank 5. Thusthe wrench in this form is of uniform diameter from end to end.

In Figs. 15 to 17 is illustrated a further modification, in which thehandle-socketed end of the wrench is actually enlarged in diameter. Inthis instance, the male die member includes cylindrical portion ll",slidably receivable within die bore 20". and portion l6" shaped forreception within the blank 5, which again is like the original blank ofthe previously described form of the invention. The male die member inthis instance is not provided with a square shank like the shank IB ofFig. 3.

The upper or female die structure includes die block l9", which is to beunderstood to be like the die block IQ of Fig. 3 excepting for notedmodification. The bore 20" extending upwardly into block l9" leads to anenlarging offset or outwardly and upwardly inclined shoulder 22", whichconnects bore 20" with a bore 2| of increased diameter, being equal tothe diameter of the finished handle receiving portion of the socketwrench. The bore 2|" is to be understood as continuing upwardly throughthe upper end of the die block, like the bore 2! of Fig. 3.

The hollow ejector tube 23 of the form of Fig. 3 is replaced by asolidcylindrical member 23", which, except for being solid rather thanhollow, may have its upper end arrangements and mounting the same asthose provided for the ejector tube 23 in the case of Fig. 3.Additionally, the lower end of the cylinder 23" has an integrally formeddownwardly projecting male die element or stem l8" of squarecross-section and of a size equal to the desired wrench handle socket,which size in this instance is greater than the initial opening insidethe blank 5. The lower end of the stem I8" has a tapered or beveled nosel8a" capable of entry inside the blank 5.

Operation of the form of Figs. 15 and 16 is as follows: The descendingfemale die assembly, carrying with it the member 22" and squared stemi8", forces the latter inside the upper portion of the blank 5,expanding the blank to an outside diameter equal to the diameter of theenlarged bore 2| The shoulder 40 at the juncture of stem IS" withcylindrical member 23" eventually engages the upper end of the blank,forcing the metal of the blank above the die shoulder 22" downwardly andlaterally or inwardly so as to conform to the square stem IS". Thedescribed reduction in length of the blank furnishes the metal requiredfor the expansion in diameter as well as that required to convert thehandle-receiving portion from 12 point" to square form. Fig. 17 showsthe completed socket wrench 6" having the enlarged portion 1" formedwith the square handle-receiving socket 8.

As will appear, the several forms of my invention have in common thepreserving of the initial interior bolt head or nut-receiving portion ofthe wrench while shortening the length of and converting the interior ofthe remaining portion of the Wrench to form a handle receiving socket,the additional metal required for the socket being obtained, at least inpart, from the shortening operation. In the preferred, first-describedform of the invention, the handle socket portion of the wrench is formedby additionally reducing the diameter thereof, so that additional metalis available for conforming the wrench to the socket formation, and notso much reduction in length is required.

I claim:

1. A method of making socket wrenches, char acterized by: forming anelongated tube having interior nut engaging faces and corners; severingsaid tube into blanks of predetermined length; and upsetting andreducing the diameter of one end portion of said blank to form aconstricted handle receiving socket while retaining the other endportion of said blank in substantially its initial form.

2. A method of making socket wrenches, characterized by: drawing anelongated tubing having corners; severing said tube into blanks ofpredetermined lengths; and hot pressing one end portion of each of saidblanks by constriction about a mandrel to form a handle receiving socketwhile restraining the other end portion of said blank against alterationof the form of its internal nut engaging faces.

4. A method of making socket wrenches, characterized by: forming atubular blank of uniform cross section having internal nut engagingfaces and corners extending from end to end; and deforming one endportion only of the blank by constriction and compression about amandrel while restraining the other end against deformation to form ahandle receiving socket of smaller size than the initial opening throughthe tubular blank.

5. A method of making socket wrenches, characterized by: formingsimultaneously and uniformly from end to end the exterior cylindricalwall and interior nut engaging faces and corners of a tubular blankadapted to receive a nut; and deforming one end portion only of theblank by constriction and compression about a mandrel while restrainingthe other end against deformation to form a handle receiving socket ofsmaller size than the initial opening through the tubular blank.

6. A method of making socket wrenches characterized by: forming anelongated tube having from end to end a number of nut engaging faces andnut receiving corners which is a multiple of the number of corners ofthe nut to be received; cutting said tube into blanks of predeterminedlength; placing a blank so cut on a mandrel having a portion shaped inconformity with the interior of said blank and extending part waytherethrough with a close sliding fit and a stem portion of smallercross-sectional size projecting from said mandrel portion through theremaining portion of said blank; and forcing over said blank a sockethaving a portion conforming to the exterior of said blank and aconstricted portion until said constricted portion has upset said lastmentioned portion of said blank into conformity with said stem portion.

7. A method of making socket wrenches, characterized by: forming anelongated tube having interior nut engaging faces and corners extendingfrom end to end; severing said tube into blanks of predetermined length;and supporting one of said blanks over part of its length bothexternally.

and internally while reducing the remaining portion by axial and radialcompression about a mandrel to form a constricted handle receivingportion.

8. A method of making socket Wrenches, characterized by: forming anelongated tube having interior nut engaging faces and corners extendingfrom end to end; severing said tube into blanks of predetermined length;supporting'one of said blanks over part of its length both externallyand internally while reducing the remaining portion by axial and radialcompression about a mandrel to form a constricted handle receivingportion; and urging said blank axially in its entirety during forming ofsaid handle receiving portion to bear the axial extremity of saidsupported portion against a beveling face thereby to form an internalbevel. I

9. A method of making socket wrenches, characterized by: forming anelongated tube having interior nut engaging faces and corners extendingfrom end to end; severing said tube into blanks of lengths apredetermined extent longer than the wrenches to be produced; andinternally supporting one end portion of a blank against deformation ofits nut engaging faces and corners while constricting the other endportions of said blank about a mandrel of the cross-sectional form of awrench handle and simultaneously exerting end pressure against thelatter end portion of the blank to compress the length of said blank tothe finally desired wrench length.

10. A method of making socket wrenches, characterized by: forming anelongated tube having interior nut engaging faces and corners extendingfrom end to end; severing said tube into blanks of lengths apredetermined extent longer than the wrenches to be produced; andexternally and internally supporting one end portion of a blank againstdeformation while reducing and shortening the other end portion thereofby radial inward and longitudinal end pressure thereon and conformingthe inside of said reduced and shortened portions to receive a wrenchhandle.

11. A method of making socket wrenches, characterized by: forming anelongated tube havin interior nut engaging faces and corners extendingfrom end to end; severing said tube into blanks of lengths-apredetermined extent longer than the wrenches to be produced; andexternally and internally supporting one end portion of a blank againstdeformation while forming a handlereceiving socket in the other endportion thereof by applying end pressure thereto to shorten it and causea lateral displacement of metal into conformation with a male die memberpositioned inside the blank.

12. A method of, making socket wrenches, characterized by: forming atubular wrench blank having interior nut engaging faces and cornersextending from end to end; internally supporting one end portion of saidblank against deformation; and forming 'a handle-receiving socket in theother end portion thereof by applying end pressure thereto to shorten itwhile confining its outer surface to the finally desired outsidediameter and permitting a resultant lateral displacement of metal to theboundaries of the desired handle-receiving socket.

13. A method of making socket wrenches, characterized by: drawing anelongated tube having interior nut engaging faces and corners extendinglongitudinally from end to end; severing said tube into blanks ofpredetermined lengths greater than the lengths of the final wrenches;internally supporting one end portion of one of said blanks againstdeformation; and forming a handle-receiving socket in the other endportion thereof by applying end pressure thereto to shorten it whileconfining its outer surface to the finally desired outside diameter andpermitting a resultant lateral displacement of metal to the boundariesof the desired handle-receiving socket.

14. A method of making socket wrenches characterized by: first forming atubular blank having internal nut engaging faces and corners, and thensupporting the internal nut engaging faces and comers at one end portionof the blank while forming a handle receiving socket in the other endportion of the blank by applying end pressure to the blank to shorten itand to cause a displacement of metal to the predetermined boundaries ofthe handle receiving socket.

WILLIAM WALTER HAR'IMAN.

